fix modal center controls to align center

app/assets/javascripts/app/views/modal.jst.eco

@@ -22,13 +22,19 @@
       </div>
       <div class="modal-footer horizontal">
   <% if @cancel: %>
-        <a class="subtle-link standalone js-cancel" href="#/"><%- @T( 'Cancel & Go Back' ) %></a>
+        <div class="modal-leftFooter">
+          <a class="subtle-link standalone js-cancel align-left" href="#/"><%- @T( 'Cancel & Go Back' ) %></a>
+        </div>
   <% end %>
   <% for button in @centerButtons: %>
+        <div class="modal-centerFooter">
           <div class="btn <%= button.className %> align-center"><%- @T( button.text ) %></div>
+        </div>
   <% end %>
   <% if @button: %>
+        <div class="modal-rightFooter">
           <button type="submit" class="btn <%= @buttonClass %> js-submit align-right"><%- @T( @button ) %></button>
+        </div>
   <% end %>
       </div>
     </div>

app/assets/stylesheets/zammad.css.scss

@@ -4374,6 +4374,14 @@ footer {
     border: none;
   }
 
+  .modal-leftFooter,
+  .modal-centerFooter,
+  .modal-rightFooter {
+    @extend .flex;
+    @extend .horizontal;
+    @extend .start;
+  }
+
 .modal.modal--local {
   display: block;
   padding-left: 40px;
@@ -5511,6 +5519,10 @@ body.fit {
   width: 33.33%;
 }
 
+.align-left {
+  margin-right: auto;
+}
+
 .align-right {
   margin-left: auto;
 }